From owner-freebsd-stable Wed Nov 14 7: 7:52 2001 Delivered-To: freebsd-stable@freebsd.org Received: from mail.wolves.k12.mo.us (mail.wolves.k12.mo.us [207.160.214.1]) by hub.freebsd.org (Postfix) with ESMTP id E869337B405 for ; Wed, 14 Nov 2001 07:07:49 -0800 (PST) Received: from mail.wolves.k12.mo.us (cdillon@mail.wolves.k12.mo.us [207.160.214.1]) by mail.wolves.k12.mo.us (8.9.3/8.9.3) with ESMTP id JAA13590; Wed, 14 Nov 2001 09:07:47 -0600 (CST) (envelope-from cdillon@wolves.k12.mo.us) Date: Wed, 14 Nov 2001 09:07:46 -0600 (CST) From: Chris Dillon To: Bill Vermillion Cc: Subject: Re: ATA hard drives In-Reply-To: <20011114051132.A12369@wjv.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-stable@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Wed, 14 Nov 2001, Bill Vermillion wrote: > Just a comment on rotational speed. You should always check the > manfacturers specs as the design of the head can greatly affect > the speed of transfer to/from the platters. I have seen 5400 RPM > drives move data faster than 7200 RPM drives. You don't see it > often but RPM alone is not sole determining factor as much as > legend would make you think it is. Data rates aren't the only factor. It is true that higher RPM doesn't necessarily mean higher data rates since you can have a lower-RPM drive with a high areal density resulting in a higher transfer rate compared to a higher-RPM drive with lower areal density. However, the higher RPM drive does have a lower rotational latency, so it takes less time for the section of the platter with the data on it that you want to come under the head, which lowers the overall latency of the drive. -- Chris Dillon - cdillon@wolves.k12.mo.us - cdillon@inter-linc.net FreeBSD: The fastest and most stable server OS on the planet - Available for IA32 (Intel x86) and Alpha architectures - IA64, PowerPC, UltraSPARC, and ARM architectures under development - http://www.freebsd.org To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message